Melchisédech Thévenot invented the spirit level in circa 1661. While the spirit level has evolved over time, its basic components and simplicity have remained the same, attesting to its practicality. Notwithstanding more cutting-edge means for measuring for horizontalness and verticalness, the spirit level continues to be a popular and necessary tool among the construction trades, equal in utility to the hammer and saw.
As with other common tools, additions to the spirit level have increased its usefulness by making it a multipurpose tool. Because of their related functions, a number of inventions have combined the capabilities of a spirit level and a framing square into one tool.
In 1961, T. White (U.S. Pat. No. 2,998,655) obtained a patent for a “leveling square.” In 1988, M. Morrell (U.S. Pat. No. 4,761,890) obtained a patent for a tool that “combines the features of a square [and] a level.” In 1995, E. Paulson and G. Paulson (U.S. Pat. No. 5,459,935) obtained a patent for “a combination tool . . . including a square [and] a level.” In 1998, B. Acopulos (U.S. Pat. No. 5,713,135) obtained a patent for a tool that “combines the functions of a framing square [and a] level.” In 2007, R. Hios (U.S. Pat. No. 7,305,773) obtained a patent for a “combination square tool with an integrated level.” In 2009, E. Vaes (U.S. Pat. No. 7,562,463) obtained a patent for “a combination level and square.” In 2010, M. Vajentic (U.S. Pat. No. 7,854,070) obtained a patent for “a square” that contains “spirit levels.” In 2011, B. Portinen (U.S. Pat. No. 7,882,643) obtained a patent for “a square and [a] leveling tool.” In 2016, C. Harris (U.S. Pat. No. 9,360,289) obtained a patent for “a multi-purpose squaring and leveling tool.”
C. Harris' invention (U.S. Pat. No. 9,360,289) comprises “a generally trapezoidal body, angled corners, and leveling inserts” and “allows for the squaring and leveling of joints around obstacles which may present barriers to traditional squaring tools.” C. Harris' invention also comprises “a substantially straight angled first end disposed approximately 45 degrees adjacent from the first straight edge” and “a substantially straight angled second end disposed approximately 45 degrees adjacent from the first straight edge.”
Although there are some similarities, in particular C. Harris' invention (U.S. Pat. No. 9,360,289), none of the prior art matches the purpose or closely resembles the design of the present invention.